Stage 1: Project survey
The current situation survey is the first stage in the development of an information system. The main task in this phase is to find out and collect the information necessary to prepare for the resolution of the project’s requirements. The survey phase is divided into two steps:
Preliminary survey: learn the basic factors (organization, culture, characteristics, people, …) to create a premise for the development of information systems in accordance with the project and the enterprise.
Detailed survey: collect detailed information of the system (processing functions, information allowed to be imported and exported from the system, binding, basic interface, professional) for analysis and design. next.
Step 2: Set out key issues that need to be solved, such as:
How should information be entered into the system?
What is the difference between display and output data?
Constraints between the objects in the system need to be built?
What requirements must the system functions and processes meet?
What solutions should be used? The feasibility of each solution like?
From the collected information and the problems raised in the survey phase, administrators and experts will select the necessary elements to form a separate information system for businesses.
Stage 2: System analysis
The objective of the stage is to define the information and processing functions of the system, in particular as follows:
Determine the requirements of the information system, including: main – secondary functions; Operations need to be handled to ensure the accuracy, compliance with current legal documents and regulations; guaranteed processing speed and future upgradeability.
Analysis and specification of the overall functional hierarchy model through the Business Flow Diagram (BFD), from the BFD model will continue to be built into the data flow model DFD (Data Flow Diagram) through the process Functional decomposition according to the levels 0, 1, 2 in each processing cell.
Data table analysis. Need to put into the system data tables including data fields (data fields)? Determine the primary key (primary key), the foreign key (foreign key) as well as the relationship between the data tables (relationship) and the necessary data constraint.
At this stage, experts will preliminarily specify data sheets on paper to have an objective view. Thereby, determining the best solutions for the system to ensure that the requirements have been surveyed before performing on specialized software.
Stage 3: Design
Through information collected from the survey and analysis process, experts will transform into specialized software and tools to specify detailed system design. This phase is divided into two steps:
Step 1: Overall design
On the basis of the analyzed data tables and paper specifications will be designed as conceptual model by specialized software such as Sybase PowerDesigner, CA ERwin Data Modeler. By conceptual level model will give experts the most overview of the relationship between objects before converting into a physical level model.
Step 2: Detailed design
Database design: With the complete physical level model at the general design stage, it will be generated code to sql file.
Design queries, procedures, functions: collect and process input information and give accurate information according to the business.
Program interface design ensures that it is suitable for the environment, culture and requirements of the business implementing the project.
Designing program functions ensures logic in input and processing for users.
Report design. Based on the requirements of each business and current regulations, it will design appropriate report templates or allow private enterprises to create report templates right on the system.
Design controls in the form of specific messages, warnings, or errors that facilitate and strictly control the input process with the goal of increasing data accuracy.
In short, design is the application of tools, methods, and procedures to create the system model that needs to be used. The final product of the design phase is to specify the system in the form it actually exists, so that programmers and hardware engineers can easily translate into system programs and structures.
Stage 4: Implementation
This is the stage to build the system according to the identified designs. This phase includes the following tasks:
Select the database management system (SQL Server, Oracle, MySQL, …) and install the database for the system.
Select programming tools to build the system’s program modules (Microsoft Visual Studio, PHP Designer, …).
Select tools to build system interfaces (DevExpress, Dot Net Bar, …).
Write manuals, technical documents or instruction clips.
Stage 5: Testing
First of all, you have to choose a test tool.
Verify information system functional modules, convert designs into programs (software).
Information system testing.
Finally, fix the errors (if any).
Write test case as required.
The end result is a satisfactory information system in place.
Stage 6: Deployment and maintenance
Install hardware as the basis for the system.
Convert the operation of the old system to the new system, including: data conversion; arrange and arrange people to work in the system; system organization for management and maintenance.
Detecting errors and shortcomings of the information system.
Training and manuals.
Improving and editing information systems.
Upgrade the program when there is a new version.